Flat type dry cell



Aug. 30, i949. M; E. WILKE FLAT TYPE DRY CELL Filed April 3, 1946 INVENTOR.

Petented Aug. 30, 1949 mr mi: nur cELL Milton E. Wilke, Freeport, Ill., assignor to Burgess Battery Company, Freeport, lll., a corporation of Delaware Application April 3, 1946, Serial No. 659,198

l Claims. (Cl. 13G-111) This invention relates to improvements in dry cells and batteries, and particularly to improved structures for dry cells of the flat type and the batteries of such cells.

The ilat type of structure for dry cells is advantageous because it makes possible the highly elcient utilization of space.

It is the primary object of the invention to provide an improved structure for ilat dry cells and batteries of such cells whereby'the eiilciency of space utilization is increased.

It is a further object of the invention to provide an improved structure for flat dry cells in which increased anode area is presented to the electrolyte and the body of active material of the cell.

It is a further object of the invention to provide an improved structure for fiat dry cells in which the anode of increased area is eiectively separated by a non-conductive element from the body of active material, which is at a potential diierent from that of the anode.

In the drawing:

Fig. 1 is a longitudinal view, partly in section, of a multiple cell battery employing the improved structure of the invention;

Fig. 2 is a perspective view of the anode member and the associated non-conductive member which separates the anode member from the body of active material;

Fig. 3 is an enlarged fragmental view, in section, of a corner of the associated anode and non-conductive members:

Fig. 4 is a perspective view of the anode member and the associated non-conductive member before they are shaped into their final form; and

Fig. 5 is a top view of one of the cells before being assembled in the battery.

Fig. 1 shows a multiple cell battery of at cells connected in series. each designated by the numeral I0. The cells may alternatively be connected in parallel or some in parallel and some in series, as would be suitable for making a combination A and B battery. The cells IIl are of ilat rectangular shape having their smallest dimension extending in a direction longitudinally of the batteryand are arranged in juxtaposed relationship in an open top container I I composed of suitable non-conductive material, such as heavy paperboard.

commencing at the left hand end of the battery, as the same is viewed in Fig. 1, there is preferably arranged immediately against the interior surface of the end wall of container II a still sheet of suitable con-conductive material I 2 which extends transversely of the battery. Adjacent to the sheet I2 is one wall of an open top envelope or pocket I3 which envelopes the first cell I0 upon all sides except the top. The pocket I3 is composed of a thin, ilexible, non-conductive material which is resistant to the liquid of the cells, such as rubber, polymerized vinyl chloride, the copolymer of vinyl chloride and vinyl acetate, a rubber hydrochloride composition, or the like. The commercial lms of the mentioned compositions which are available upon the market are suitable for use in constructing the pockets. The manner of their construction will be described hereinafter. AWithin the pocket I3 is a compressed body Il of active material, which may be composed of powdered manganese dioxide ore and graphite or carbon, moistened with the liquid electrolyte of the cell, which may be an aqueous solution containing ammonium chloride and zinc chloride. The active body I4 is in the shape of a flat block having a height and thickness, as shown in Fig. 1, and a width several times its thickness as shown in Fig. 5. The dimensions of the body I4 are not critical and may be varied as desired, the dimensions given being merely an example of those which are suitable for a satisfactory cell.

Embedded substantially centrally withln the active body I4 and projecting upwardly from the' top of said body is the cathode I5 of the cell, which may be in the conventional form of a carbon rod having a small amount of solder 9 upon the upper end thereof. The next element in the sequence proceeding from left to right is the bibulous, non-conductive, separating member I6, which may be composed of absorbent paper, moistened with the liquid electrolyte. Said element I6 is in the form of a sheet which encloses the' and 5. The succeeding element is the metal anode I I1, which may be composed of zinc and is shaped similarly to separating member I 6 and encloses the latter upon the front, bottom and two sides.

Adiacent to the anode Il is the right hand Wall of the envelope or pocket I3, which completes the ilrst cell I0. I

The construction and arrangement of the anode I'I and the associated separating member I6 in accordance with the present invention are shown in Figs. 2 and 3. The separating member I6 has a at main body section I8'and ilanges 20 extending perpendicularly from the side and bottom edges oi the main section in such manner as to enclose the sides and bottom of the active body i4. The anode I1 is similarly shaped and has main section IB and iangesv 2i. 'I'he separating member nests snugly within the anode. The main section I9 of the anode is slightly higher than the main section I8 of the separat- 'ing member, and has spaced apart lugs 22 and 23 projecting upwardly therefrom for a purpose wihch will be explained hereinafter. As is shown in Figs. 1 and 2, the main section I8 and the side anges 2l) of the separating member I6 have a height somewhat greater than that of the active both members bend along the same lines, which extend from the corners of the notches in the anode blank in directions parallel to the edges l of said blank. The material of the separating body I4, and the side and bottom flanges have a depth substantially equal to the thickness of,

the active body I4. The separating member, therefore, completely encloses the front, bottom and two sides of the active body. The anges 20 of the separating member are somewhat longer and deeper than the flanges 2i of the anode and project beyond the edges of said flanges 2l This arrangement insures that the anode is electrically separated from the active body I4, which is at a potential different from that of the anode.

It is apparent from the foregoing description that in the improved construction ofthe present invention, active anode surface is presented to the bottom and the sides of the active body I4, in addition to the front thereof, whereby the area and quantity of active anode is increased very substantially over the amount which would be available if the anode iianges 2i were omitted. In fact, in the specific arrangement described, the active anode area is approximately doubled by the addition of the flanges. Such construction, therefore, very -materially increases the available energy which can be obtained from the battery, and represents a more eflicient utilization of the space within the' battery. Inasmuch as the nat cell type of battery is frequently employed'in situations Where the spaceloccupied must be reduced to a minimum, the construction of the invention provides an important advantage.

Means are provided at the bottom corners of the cell to insure that no active material of the body I4 comes in contact, with the anode flanges 2| through any gaps which may occur where the 'separating member flanges 2| abut each other.

As is shown in Fig. 3, the end portions 24 of the anges 20 of the separating member project into the gap between the ends of the adjacent anges 2| of the anode member.

The manner in which the association of the anode and separating member is accomplished is illustrated in Fig. 4. Flat blanks for the anode .I'I and the separating member I6 are first formed in the relative size and shape shown, the bottom corners of both being notched to the depth of the anode flanges. The two blanks are arranged as shown with the edge portions of the flange sections of the separating member blank extending beyond the corresponding edge portions of, the anode member blank, and while retaining such relationship, a rectangular jig member having a height and width approximately equal to the height and width of the active body I4 is placed against the separating member blank in the same relative position as is occupied by the active member I4 in the cell. The ange sections of the two blanks are then bent simultaneously over the jig by any suitable means to a position perpendicular to the main sections of the blanks. In this operation, the relative arrangement of the two members shown in Figs. 2 and 3 is automatically formed. The edge portions 24 at the ends member iianges located inwardly of the corner of the notch in said member does not wrinkle or bunch, but is compressed together 'against the jig and forms a dat rectangular corner of solid material at the base of the anges. From the 'y corner of the separating member notch outwardly, the material of said member extends a progressively increasing distance into the gap between the adjacent ends of the anode ilanges, as shown at 24 in Fig. 3. A tight fit is formed which serves as a gasket through which it is substantially impossible ior any of the material of the active body I4 to pass, whereby short circuits between the active body and the anode are prevented.

A suitable method for enclosing the cells IG in the pockets I3 is illustrated in Fig. 5. A sheet I3 of the exible' non-conductive material of the proper width is arranged with its midsection against the bottom of the cell and is folded upwardly so that it covers the bottom and the iront and back of the cell. The material of the sheet is then folded inwardly over the sides of the cell until the portion extending from the front meets the portion extending from the back, when the portions are folded outwardly in contact with each other and are pressed together and adhesively joined to form the joints 3D which complete pocket I3. In the completed battery, the joints 3B are folded against the sides of the cells so as to occupy a minimum of space.

The construction and arrangement of the next succeeding cell is the same as has been described, the second pocket I3 being arranged adjacent to the irst Vpocket and the elements of the cell being arranged within the pocket in the manner which has been described. The remaining cells are assembled in a similar manner, the arrangement'of the nal assembly being such that the cells are under compression in a direction longitudinally of casing II. The terminal lug 22 of the anode I1 of the rst cell is bent horizontally to the right and into contact with the cathode I5 of the second cell, suitable electrical connection between said anode and cathode being made by momentarily heating the end portion of the lug 22 in such manner as to melt the solder tip 9, whereby said tip forms a solder joint between the electrodes. vThe two cells are thereby connected in series vand. the remaining cells are connected in series in a similar manner. A conductor 25 is suitably connected to the cathode I5 of the first cell and extends around the outside of the container II and is connected to the termina] 26 of the conventional socket-type of terminal member 28, which is arranged exteriorly adjacent to the righthand end of container II. In a similar manner, a conductor 29 is suitably connected to the anode II of the last cell and extends to the exterior of container II and is connected to the terminal 2l of terminal member 28. A seal closure 3I closes the open tops of the cells I D and the container Il to form a common seal 'spirit of the invention. For

for the cells and the battery. Closure 3| may be composed of the usual fusible wax or pitch sealing composition, which may be poured into place in the molten condition.

The second lug 23 extending upwardly froml each of the anodes I1 projects through the closure 29 and the end thereof is exposed. After the battery has been formed as described, it is preferably aged for a number of days or weeks and the cells are then tested individually for defects by connecting a voltmeter between the lugs 23 of adjacent cells. After the battery has been completed and tested, it is enclosed in an outer carton 32 of suitable non-conductive composition, such as heavy paperboard. The battery terminal 28 is exposed through an opening 33 in the end of the carton 32.

While a single embodiment of the invention has been described, this is for purposes of illustration, and the invention is not limited thereto. Various modifications may be made in the structure and composition of the cells and the battery and the parts thereof without departing from the example, the cells may be of other than the rectangular shape shown. Also, the testing lugs 23 may be omitted. Also, means dierent from the pockets I3 may be employed for physically isolating the indivdual cells. The structure of pockets I3 does not form a part of the invention. In a similar manner, other modifications may be made in the construction of the battery and the parts thereof.

What is claimed is:

1. In a dry cell, a body of active material having flat sides, a fiat metal electrode adjacent to a side of said active body, and a separating sheet of bibulous non-conductive material between said active body and said electrode, said metal electrode and said bibulous sheet having anges along adjacent edges thereof enclosing additional sides of said active body, the material of said bibulous sheet extending between the flanges of said metal electrode at the junctions of said flanges.

2. In-a dry cell, a body of active material having flat sides, a fiat metal electrode adjacent to a. side of said active body, and a separating sheet of bibulous non-conductive material between said active body and said electrode, said metal electrode and said bibulous sheet having anges along adjacent edges thereof enclosing additional sides of said active body, the material of said bibulous sheet extending between the ends of adjacent flanges of said metal electrode and forming a gasket between said flange ends.

3. In a dry cell, a body of active material having flat sides, a flat metal electrode adjacent to a side of said active body, and a separating sheet of bibulous, non-conductive material between said active body and said electrode, said metal electrode and said bibulous sheet having flanges along adjacent edges thereof enclosing additional sides of said active body', the adjacent ends of the flanges of said metal eelctrode being in proximity to each other, the end portions of the flanges of said bibulous sheet` extending into and subthe bottom and two sides stantially lling the crevices between said adiacent ends of the flanges of said metal electrode.

4. Ina dry cell. a body of active material having flat surfaces consisting of a front, back, top, bottom and two sides, a flat jacent to the front of said active body, and a separating sheet of bibulous, non-conductive material between said active body and said electrode, said metal electrode and bibulous sheet having flanges along three adjacent edges thereof encompassing material of said bibulous sheet extending between the ends of adjacent flanges of said metal electrode and forming a gasket between said ange ends, and a second electrode projecting from the top of said active body.

5. In a dry cell, a body of active material having flat surfaces consisting of a front, back and two sides, a nat metal electrode adjacent to the front of said active body, and a separating sheet of bibulous, non-conductive material between y said active bodyV and said electrode, said metal electrode and bibulous sheet having flanges along three adjacent edges thereof encompassing the bottom and two sides of said active body, the material of said bibulous sheet extending between the ends of adjacent flanges of said metal electrode and forming a gasket between said flange ends. y

6. A negative electrode for a dry cell comprising a metallic plate having a flat rectangular area, side flanges extending at right angles from the long sides of. said area, and an end flange .extending Yat a right angle from a short side of said area, the ends of said end flange being near but spaced from the contiguous ends of said side flanges.

7. In a dry cell. a metal electrode having a ilat body portion and flanges along three adjacent sides of said body portion, a layer of bibulous non-conductive material lining said body and flanges, a body of active material having flat sides in contact with said bibulous layer and enclosed the foregoing assembly on all sides except the exposed edge of said active body, and an elongated conductive terminal embedded in said active body and projecting from said exposed edge of said active body.

` MILTON E. W'ILKE.

' REFERENCES crrED The following references are of record in the file of this patent:

UNITED STATES PATENTS metal electrode adof said active body, the

Certificate of Correction Patent No. 2,480,531 August 30, 1949 MILTON E. WILKE It is hereby certified that errors appear in the printed speccation of the above numbered patent requiring correction as follows:

Column 5, line 64, for eelctrode read electrode; column 6, line 18, after the Word back insert top, bottom;

the same may conform to the record of the ease in the Patent Oce.

Signed and sealed this 17th day of January, A. D. 1950.

THOMAS F. MURPHY,

Assistant Uommz'ssz'oner of Patents. 

